This is, I know, nit picking. The spec says
# Starting from the center and progressing towards (and potentially
# beyond) the ending shape concentric ellipses are drawn and colored
# according to the specified color stops.
I am not sure this is well-defined as I don't know if concentric
ellipses are by definition necessarily having the same eccentricity.
I don't mean to use www-style as a Math forum but oddly enough I
couldn't find the definition of "concentric ellipses" on Google. I
searched "are concentric ellipses always having the same eccentricity"
and did find sentences like "a group of concentric ellipse having the
same eccentricity and axis slope" or "the ellipses are concentric with
the same eccentricity", so I guess this paragraph would need be extended
a bit (also, the orientation/axis slope should be fixed).
Cheers,
Kenny